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* [PATCH] soundwire: cadence: do not extend reset delay
@ 2021-08-18  3:01 Bard Liao
  2021-08-23 12:12 ` Vinod Koul
  0 siblings, 1 reply; 2+ messages in thread
From: Bard Liao @ 2021-08-18  3:01 UTC (permalink / raw)
  To: alsa-devel, vkoul
  Cc: vinod.koul, linux-kernel, gregkh, srinivas.kandagatla,
	pierre-louis.bossart, sanyog.r.kale, bard.liao

From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>

The duration of the hw_reset is defined as 4096 cycles. The Cadence IP
allows for an additional delay which doesn't seem necessary in
practice: the actual reset sequence duration is defined by the sync_go
mechanism, not by the IP itself.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
---
 drivers/soundwire/cadence_master.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c
index 0b7f037e6cd0..4fcc3ba93004 100644
--- a/drivers/soundwire/cadence_master.c
+++ b/drivers/soundwire/cadence_master.c
@@ -1032,10 +1032,7 @@ EXPORT_SYMBOL(sdw_cdns_check_self_clearing_bits);
  */
 int sdw_cdns_exit_reset(struct sdw_cdns *cdns)
 {
-	/* program maximum length reset to be safe */
-	cdns_updatel(cdns, CDNS_MCP_CONTROL,
-		     CDNS_MCP_CONTROL_RST_DELAY,
-		     CDNS_MCP_CONTROL_RST_DELAY);
+	/* keep reset delay unchanged to 4096 cycles */
 
 	/* use hardware generated reset */
 	cdns_updatel(cdns, CDNS_MCP_CONTROL,
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 2+ messages in thread

* Re: [PATCH] soundwire: cadence: do not extend reset delay
  2021-08-18  3:01 [PATCH] soundwire: cadence: do not extend reset delay Bard Liao
@ 2021-08-23 12:12 ` Vinod Koul
  0 siblings, 0 replies; 2+ messages in thread
From: Vinod Koul @ 2021-08-23 12:12 UTC (permalink / raw)
  To: Bard Liao
  Cc: alsa-devel, linux-kernel, gregkh, srinivas.kandagatla,
	pierre-louis.bossart, sanyog.r.kale, bard.liao

On 18-08-21, 11:01, Bard Liao wrote:
> From: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
> 
> The duration of the hw_reset is defined as 4096 cycles. The Cadence IP
> allows for an additional delay which doesn't seem necessary in
> practice: the actual reset sequence duration is defined by the sync_go
> mechanism, not by the IP itself.

Applied, thanks

-- 
~Vinod

^ permalink raw reply	[flat|nested] 2+ messages in thread

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